The present invention relates to the art of preparing shredded grain product, and, in particular, concerns improved apparatus and method of cutting and scoring shredded grain product in the plastic or pulpy state.
Devices for making shredded cereal products are well known. In the conventional process a grain, such as wheat or a combination of wheat and other grain is first softened by cooking and tempering, and is fed into each of a series of shredding mills. The conventional shredding mill comprises a pair of closely spaced rolls that rotate in opposite directions, with at least one of the rolls having circumferential grooves. Upon passing between the rolls, the wheat is deformed into long individual strings or shreds. In some procedures, the rolls have cross grooves as well as circumferential grooves in order to achieve a web effect rather than merely a single strand.
The shredding mills are arranged in a linear series across a common conveyor, with the shreds running longitudinally or in parallel with the direction of movement of the conveyor.
Having obtained the requisite web thickness, the multiple layer web can be cut and scored to provide a continuous line of biscuits having edges which are partially cut and crimped whereby, upon baking, the grain product is sealed along the crimped edges to form individual shredded grain pieces. Thus, the cutting operation serves to provide separation of the individual pieces and to seal the severed edges.
For example, U.S. Pat. No. 4,004,035 to Hirzel, et al. discloses a method for formation of a shredded food article in the form of a biscuit by depositing a web of longitudinally shredded food transversely across a moving bed in a uniform overlapping zig-zag configuration whereby a wider, continuous, multiple layer sheet is formed. The sheet is then cut longitudinally following by transversely cutting the sheet to produce a plurality of files and rows of lapped shredded biscuits on a moving bed.
Another method of making a shredded cereal product includes formation of a cereal dough which is kneaded, worked and cooked while passing through an extruder-heat exchanger preferably through a die having a circular arrangement of closely adjacent orifices thereby discharging a cylindrical arrangement of dough strands. See U.S. Pat. No. 3,054,677 to Graham, et al. See also U.S. Pat. Nos. 991,584 and 931,243 to Williams which disclose use of circular cups or baking forms wherein shredded grain product is deposited for baking.
A major disadvantage of conventional systems is the extensive outlay in capital equipment required for a single biscuit line. Large scale production requires a number of separate lines, each with its own series of shredding mills, conveyor, cutting and handling devices.
Another drawback with the conventional process is the inherent limitation on possible biscuit sizes, especially since shredding rolls have a fixed width and are capable of producing a shred layer of only a single width. Although the shredded web may be subdivided longitudinally as well as being cut transversely, possible piece size variations are substantially limited. A major change in biscuit size might very well require a costly replacement of shredding mills.
In the case of cutting the web by press type cutters or rotating contact cutters in which individual blades contact the web at regular intervals, continuous production is hampered by limited tensile strength and stickiness of the shredded material which causes the material to adhere to the blade or prevents the blade from properly severing the material. Moreover, air blow-off systems are required to effect separation of the web from the cutter which are energy consuming and which cause breakage of the product. Thus, although a range of products can be successfully shredded in shredding mills, only those products possessing rather specific properties in shredded form can be successfully shaped by conventional procedures.
It is, therefore, an object of the present invention to provide a smooth running rotary cutter assembly which will cut a continuous web of multi-layered shredded grain product without the problems normally associated with cutting a web of shredded grain product.